/*
 * Copyright (C) 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.pachong.android.baseuicomponent;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.support.v4.view.ViewCompat;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;

import com.pachong.android.baseuicomponent.adapter.RecyclerViewBaseAdapter;


public class DividerItemDecoration extends RecyclerView.ItemDecoration {

    private static final int[] ATTRS = new int[]{
            android.R.attr.listDivider
    };

    public static final int HORIZONTAL_LIST = LinearLayoutManager.HORIZONTAL;

    public static final int VERTICAL_LIST = LinearLayoutManager.VERTICAL;

    private Drawable mDivider;

    private int mOrientation;

    public DividerItemDecoration(Context context, int orientation) {
        final TypedArray a = context.obtainStyledAttributes(ATTRS);
        mDivider = a.getDrawable(0);
        a.recycle();
        setOrientation(orientation);
    }

    public void setOrientation(int orientation) {
        if (orientation != HORIZONTAL_LIST && orientation != VERTICAL_LIST) {
            throw new IllegalArgumentException("invalid orientation");
        }
        mOrientation = orientation;
    }

    @Override
    public void onDraw(Canvas c, RecyclerView parent) {
        if (mOrientation == VERTICAL_LIST) {
            drawVertical(c, parent);
        } else {
            drawHorizontal(c, parent);
        }
    }

    public void drawVertical(Canvas c, RecyclerView parent) {
        final int left = parent.getPaddingLeft();
        final int right = parent.getWidth() - parent.getPaddingRight();

        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++) {
        	if(!shouldDrawItemAt(parent, i)) {
        		continue;
        	}
            final View child = parent.getChildAt(i);
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child
                    .getLayoutParams();
            final int top = child.getBottom() + params.bottomMargin +
                    Math.round(ViewCompat.getTranslationY(child));
            final int bottom = top + mDivider.getIntrinsicHeight();
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }

    public void drawHorizontal(Canvas c, RecyclerView parent) {
        final int top = parent.getPaddingTop();
        final int bottom = parent.getHeight() - parent.getPaddingBottom();

        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++) {
        	if(!shouldDrawItemAt(parent, i)) {
        		continue;
        	}
            final View child = parent.getChildAt(i);
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child
                    .getLayoutParams();
            final int left = child.getRight() + params.rightMargin +
                    Math.round(ViewCompat.getTranslationX(child));
            final int right = left + mDivider.getIntrinsicHeight();
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }

    @Override
    public void getItemOffsets(Rect outRect, int itemPosition, RecyclerView parent) {
    	//Add for ignore header view and footer view offsets
    	if(!shouldDrawItemAtAdapterPosi(parent, itemPosition)) {
    		  outRect.set(0, 0, 0, 0);
    		return;
    	}
    	//End added
    	
        if (mOrientation == VERTICAL_LIST) {
            outRect.set(0, 0, 0, mDivider.getIntrinsicHeight());
        } else {
            outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0);
        }
    }
    

	/**
	 * 判断是否要draw item
	 * e.g headerview 和 footerview就不用画item decoration
	 * 
	 * @param itemPosi
	 *            某个位置 layout position, not adapter position
	 * @return
	 */
	private boolean shouldDrawItemAt(RecyclerView parent, int itemPosi) {
		RecyclerView.ViewHolder vh = parent.getChildViewHolder(parent.getChildAt(itemPosi));
		if (vh instanceof RecyclerViewBaseAdapter.HeaderViewHolder) {
			//return false;
		}
        return !(vh instanceof RecyclerViewBaseAdapter.LoadingViewHolder);
    }


	/**
	 * 判断是否要draw item
	 * e.g headerview 和 footerview就不用画item decoration
	 * 
	 * @param itemPosi
	 *            某个位置adapter position, not layout position
	 * @return
	 */
	private boolean shouldDrawItemAtAdapterPosi(RecyclerView parent, int itemPosi) {
		RecyclerView.Adapter adapter = parent.getAdapter();
		if (adapter != null && adapter instanceof RecyclerViewBaseAdapter) {
			RecyclerViewBaseAdapter rvBaseAdapter = (RecyclerViewBaseAdapter)adapter;
			if (itemPosi == 0 && rvBaseAdapter.hasHeaderView()) {
				//return false;
			}
			if (itemPosi == rvBaseAdapter.getItemCount() - 1 && rvBaseAdapter.hasLoadingLayout()) {
				return false;
			}
		}
		return true;
	}
}
